Jam resistant door lock



Se t. 2, 1969 F. G. RUCKEL ET 3,464,723

JAM RESISTANT DOOR LOCK Filed July 21, 1967 3 Sheets-Sheet l 1 NVENTORS FERN/f G. PUC/(EL DHl/ID F0 X BY JWZM fi TTORNEY Sept. 2, 1969 5, RUCKEL ET AL 3,464,728

JAM RESISTANT DOOR LOCK Filed July 21, 1967 3 Sheets-Sheet 2 WNW ii/5.3%? L INVENTORS FHDNK G. RUCHEL DRt/ID FOX flTTORNEY Sept. 2, 1969 F. G. RUCKEL ET AL JAM RESISTANT DOOR LOCK 3 Sheets-Sheet Filed July 21, 1967 INVENTORS FRANK G. RUCPfEL DAVID (K -*1 M .BTTOPNEY FOX 3,464,728 JAM RESISTANT DOOR LOCK Frank G. Ruckel, Floral Park, and David Fox, Bayside, N.Y., assignors to Alarm Lock Corporation, Roslyn Heights, N.Y.

Filed July 21, 1967, Ser. No. 655,086 Int. Cl. Ec 15/02; E05b 15/02 U.S. Cl. 29292 9 Claims ABSTRACT OF THE DISCLOSURE A door lock and bolt for emergency use in which the bolt face and the keeper plate face are disposed at angles in relation to the plane of the door.

BACKGROUND OF THE INVENTION Field of the invention.Panic-proof door locks for use in emergency exit doors.

Description of the prior art.The prior art abounds with various lock mechanisms which are designed to unlock a door and permit its opening during such emergency conditions as persons seeking emergency egress. Cross bars which are adapted to be depressed under the pressure of crowds and thereby withdraw the lock bolt from its keeper and thereby permit the door to swing outwardly open are well known to the prior art.

SUMMARY OF THE INVENTION The very same crowd pressure which is intended to depress the cross bar also, however, simultaneously forces the door outwardly and very frequently jams the bolt in the keeper. Unless the crowd pressure is selectively withdrawn from the door and used exclusively against the cross bar, an unlikely occurrence, it is exceedingly improbable that the bolt will be withdrawn from its keeper and the door permitted to open.

Accordingly it is an object of the present invention to provide a jam-proof bolt and keeper configuration.

It is another object of the present invention to provide a bolt and keeper system which will permit withdrawal of the bolt regardless of the pressure which may be exerted between the bolt and the keeper.

Briefly, and not by way of limitation, the present invention comprises a bolt face on the outward opening side of the door which is at an acute angle with respect to the plane of the door. The keeper plate has a mating surface also angularly disposed at an angle which may or may not be the same as the angle of the bolt face. Either the bolt face or the keeper plate mating surface, or both, may be curved convexly toward each other. Either the bolt face or the keeper plate mating surface, or both, may have bearings or belts.

The present invention is intended to materially reduce, if not virtually completely eliminate, friction between the bolt face and the keeper plate mating surface thereby permitting jam-proof withdrawal of the former from the latter; nevertheless, the security of the door lock with the bolt in its extended position is in no way impaired.

BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 is a plan view of a door showing the door lock and cross bar of the present invention mounted thereon.

FIGURE 2 is a cross-sectional view taken across line 22 of FIGURE 1.

FIGURE 3 is a cross-sectional view similar to that of FIGURE 2 wherein the cross bar has been depressed to retract the bolt thereby permitting opening of the door as indicated.

States Patent 0 3,464,728 Patented Sept. 2, 1969 FIGURE 4 is an enlarged fragmentary view, partly in phantom, of the door lock shown in FIGURE 1 with the cover plate removed therefrom.

FIGURE 5 is a partial cross-sectional view taken across line 55 of FIGURE 4.

FIGURE 6 is a partial cross-sectional view as taken across line 66 of FIGURE 4.

FIGURE 7 is a partial cross-sectional view similar to that of FIGURE 6 showing the cross bar depressed and the bolt in retracted position.

FIGURE 8 is a plan view of a keeper plate of the present invention.

FIGURE 9 is a fragmentary partial cross-sectional View of a first modified form of the present invention in which the keeper plate engagement surface consists of a field of ball bearings.

FIGURE 9A is a cross-sectional view of the keeper plate engagement surface as taken across line 9A9A of FIGURE 9.

FIGURE 10 is a fragmentary partial cross-sectional view of a second modified form of the present invention in which the keeper plate engagement surface' consists of a plurality of roller bearings.

FIGURE 10A is a cross-sectional view of the engagement surface of the keeper plate of the second modified form of the present invention as taken across line 10A 10A of FIGURE 10.

FIGURE 11 is a third modified form of the present invention in which the keeper plate engagement surface consists of an endless belt.

FIGURE 11A is a cross-sectional view of the engagement surface of the keeper plate of the third modified form of this invention as taken across line 11A-11A of this invention.

FIGURE 12 is a fragmentary partial cross-sectional view of a fourth modified form of the present invention in which the engagement surface of the bolt consists of a roller bearing.

FIGURE 12A is a fragmentary view of the engagement surface of the bolt of the fourth modified form of the present invention as viewed across line 12A12A of FIG- URE 12.

FIGURE 13 is a fragmentary partial cross-sectional view of a fifth modified form of the present invention in which the engagement surface of the bolt and the keeper plate are outwardly or convexly curved with respect to each other.

Description of a preferred embodiment Referring to the drawing the jam resistant door lock 10 of the present invention comprises a lock mechanism enclosure 12, a cross bar 14 and a keeper plate 16 disposed in the usual locations with respect to each other. Cross bar 14 extends substantially horizontally across the interior surface of an outwardly opening door and is intended to be operable under adverse conditions, such as a panicked mob seeking emergency egress.

The cross bar 14 is pivotally connected to two pivoting arms 18 and 20 each of which has a vertical pivot axis located within enclosure 12 substantially equi-distant from the plane of the door. The resulting parallelogram defined by the four pivot points, two of which just described and two of which connect bar 14 to arms 18 and 29, locate cross bar 14 substantially parallel to the plane of the door. The pivot axes being vertical, cross bar 14 may be operated by horizontal pressure directed perpendicularly toward the plane of the door.

Door bolt 3!) is horizontally slidably disposed parallel to the plane of the door and has a locking sear 32 and a cam follower 34 secured thereto. Pivoting arm 20 has a locking arm 22 which normally engages locking sear 32 so as to prevent retraction of bolt 30. As cross bar 14 is depressed toward the door locking arm 22 pivots away from and out of engagement with locking sear 32.

Attached to cross bar 14 is a cam 24 which, as cross bar 14 is depressed, engages cam follower 34 to slidably retract bolt 30. As may be determined from FIGURES 6 and 7, cross bar 14 not only has a vector of motion perpendicular to the plane of the door but also has a vector of motion horizontally parallel to the plane of the door, the resultant horizontal diagonal vector of motion first unlocking bolt 30 and then retracting bolt 30.

Bolt 30 has an angularly disposed mating or engagement surface 40 which is on the outwardly facing side of bolt 30. Keeper plate 16 also has an angularly disposed mating or engaging surface 50 which is on the side of the keeper plate adjacent the exterior and which faces inwardly toward the interior so as to meet or engage engagement surface 40 of bolt 30 when the door is pushed outwardly in an attempt to be opened.

In the basic embodiment of the present invention engagement surfaces 40 and 50 are vertical planes disposed at an acute angle with respect to the plane of the door. The purpose of those angular orientations is clear; the tendency of the bolt to jam in the keeper is substantially and materially reduced by reason of the reduction in friction between the respective engaging surfaces.

The precise angular dispositions of each of the engagement surfaces with respect to the plane of the door (when, of course, the door is closed) are matters of choice Within our broad concept herein taught. It has been determined by experimentation, however, that the following particular angular dispositions may be most advantageous: the angle of keeper plate engagement surface 50 with respect to the plane of the door, approximately 30"; the angle of bolt engagement surface 40 with respect to the plane of the door, approximately 35. The advantages of such angular dispositions may be seen in FIGURES and 6. The engaging surfaces meet in linear rather than area contact thereby further reducing frictional resistance to retraction of bolt 30.

Description of a first modified embodiment Referring to FIGURES 9 and 9A, bolt 130 of the first modified embodiment has an engagement surface 140 which is quite similar to that of the primary embodiment, being planar and disposed vertically at an acute angle with respect to the plane of the door.

Engagement surface 150 of keeper plate 116 consists of a field of ball bearings arranged for contact with bolt engagement surface 140. Accordingly, when bolt 130 is retracted under the pressure applied to cross bar 14, there is a virtually complete absence of friction between bolt 130, keeper plate 116 and the respective engagement surfaces 140 and 150. The engagement surfaces 140 and 150 are substantially parallel.

Description of a second modified embodiment Referring to FIGURES l0 and 10A, the jam resistant door lock in its second modified form comprises a bolt 230 similar to the bolt of the primary embodiment, having a planar angularly disposed engagement surface 240.

The keeper plate 216 of this embodiment has an engagement surface 250 which consists of a plurality of roller bearings which are vertically aligned to define a plane located at an acute angle with respect to the door, that angle being the same as the angle between the plane of engagement surface 240 and the plane of the door.

It is accordingly apparent that there is exceedingly little friction between engagement surface 240 and engagement surface 250 whereby retraction of bolt 230 is accomplished under emergency conditions with relative ease and without jamming.

4 Description of a third modified embodiment In the third modified embodiment of the present invention bolt 330 again is substantially similar to the bolt of the primary embodiment, having a planar engagement surface 340 vertically located at an acute angle with respect to the plane of the floor.

Keeper plate 316 has an engagement surface 3-50 which consists of an endless belt the engaging surface of which is plane parallel to the plane of engagement surface 340. The endless belt extends around two end rollers the axes of rotation of which are vertical and define a plane which is parallel to the plane of engagement surface 340'. It may again be seen that there will be very little resistance to retraction of bolt 330 under pressure applied to cross bar 14.

Description of a fourth modified embodiment In the fourth modified embodiment of the present invention keeper plate 416 and its angularly disposed planar engagement surface 450 are substantially similar to those members of the primary embodiment.

Bolt 430 has an engagement surface 440 which comprises a roller bearing rotationally secured within'bolt 430 for rolling engagement with engagement surface 450 again, frictional resistance to retraction of bolt 430 is minimized.

Description of a fifth modified embodiment In the fifth modified embodiment of the present invention engagement surface 540 of bolt 530 and engagement surface 550 of keeper plate 516 are both curved convexly one toward the other. The resulting contact between the engageemnt surfaces is reduced from the relatively high friction area contact to the relatively low friction linear contact in the case of cylindrical engagement surfaces and is reduced to the even less frictional resistance of point contact in the case of spherical engagement surfaces.

While the foregoing is illustrative of several embodiments of this invention it is clear that other forms and modified embodiments may be had within the broad spirit of the invention. For example, in the fifth modified embodiment shown in FIGURE 13 both engagement surfaces are convexly curved. It is entirely feasible, however, to have only one of such engagement surfaces conwexly curved toward the other while the other of such surfaces is planar. Also for example, the keeper plate engagement surface 450 of the fourth modified embodiment may be curved convexly toward the bolt engagement surface 440. Further, for example, the respective engagement surfaces of the primary embodiment may be parallel.

What is claimed is:

1. A jam resistant door lock for use on an outwardly opening door, comprising:

a retractable bolt, said retractable bolt being engaged and retracted by a cross bar having movement under pressure substantially parallel to the direction of retraction;

an engagement surface on said retractable bolt, said engagement surface being substantially vertical and angularly disposed with respect to the plane of the door;

a keeper plate;

an engagement surface on said keeper plate, said engagement surface being disposed substantially vertical and at an angle with respect to the plane of the door when the door isclosed, said keeper plate engagement surface and said bolt engagement surface being adapted to engage each other when pressure is applied to the door to open the same.

2. A jam resistant door lock for use on an outwardly opening door in accordance with claim 1, wherein said bolt engagement surface is planar and said keeper plate engagement surface is planar and parallel to the plane of the bolt engagement surface.

3. A jam resistant door lock for use on an outwardly opening door in accordance with claim 1, wherein said bolt engagement surface is planar and said keeper plate engagement surface is planar and diverges from said bolt engagement surface in an inward direction.

4. A jam resistant door lock for use on an outwardly opening door in accordance with claim 2, wherein said keeper plate engagement surface comprises a field of ball bearings.

5. A jam resistant door lock for use on an outwardly opening door in accordance with claim 2, wherein said keeper plate engagement surface comprises at least one roller bearing, the axis of rotation of which is vertical and located in a plane which is parallel to the plane of said retractable bolt engagement surface.

6. A jam resistant door lock for use on an outwardly opening door in accordance with claim 2, wherein said keeper plate engagement surface comprises a moveable endless belt, said endless belt having two end rollers, the axes of rotation of which are vertical and located in a plane which is parallel to the plane of said retractable bolt engagement surface.

7. A jam resistant door lock for use on an outwardly opening door in accordance with claim 1, wherein said retractable bolt engagement surface comprises at least one roller bearing, the axis of rotation of which is vertical and located ina plane which is parallel to the plane of said keeper plate engagement surface.

8. A jam resistant door lock for use on an outwardly opening door in accordance with claim 1, wherein one of said engagement surfaces is convexly curved toward the other engagement surface.

9. A jam resistant door lock for use on an outwardly opening door in accordance with claim 1, wherein said keeper plate engagement surface and said retractable bolt engagement surface is each convexly curved toward the other.

References Cited UNITED STATES PATENTS 2,087,165 7/1937 Ruth 29292 2,320,298 5/ 1943 Phillips 29292 3,206,954 9/1965 Snyman 29274 X FOREIGN PATENTS 613,580 11/1948 Great Britain.

RICHARD E. MOORE, Primary Examiner U.S. Cl. X.R. 292--34O 

